Make a self-control roll whenever you have an opportunity to indulge your desires and know you shouldn’t (e.g., because the prisoner is one who should be released unharmed). If you fail, you cannot restrain yourself.
Make a self-control roll each day. If you fail, you must try to trick a dangerous subject: a skilled warrior, a dangerous monster, a whole group of reasonably competent opponents, etc. If you resist, you get a cumulative -1 per day to your self-control roll until you finally fail a roll!
